#include <fstream>
#include <iostream>
#include <list>
#include <queue>
#include <vector>

using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");

struct graf{
    list<int> vecini;
} nod[100005];
queue<int>q;
int n,m,start,i,x,y,viz[100005],nrc;


void DFS(int x)
{
    viz[x]=1;
    for(list<int>::iterator it=nod[x].vecini.begin();it!=nod[x].vecini.end();++it)
            if(viz[*it]==0)
                DFS(*it);
}


int main()
{
    fin>>n>>m;
    for(i=1;i<=m;i++)
    {
        fin>>x>>y;
        nod[x].vecini.push_back(y);
        nod[y].vecini.push_back(x);
    }

    for(i=1;i<=n;i++)
        if(viz[i]==0)
        {
            DFS(i);
            ++nrc;
        }

    fout<<nrc;

    return 0;
}